Grains, especially whole grains, are an essential part of a healthy diet. All types of grains are good sources of complex carbohydrates and some key vitamins and minerals. Grains are also naturally low in fat. All of this makes grains a healthy option. Better yet, they've been linked to a lower risk of heart disease, diabetes, certain cancers and other health problems.

The healthiest kinds of grains are whole grains. The Dietary Guidelines for Americans recommends that at least half of all the grains you eat are whole grains. Chances are you eat lots of grains already. But are they whole grains? If you're like most people, you're not getting enough whole grains in your diet. See how to make whole grains a part of your healthy diet.

Types of grains

Also called cereals, grains and whole grains are the seeds of grasses cultivated for food. Grains and whole grains come in many shapes and sizes, from large kernels of popcorn to small quinoa seeds.

Whole grains. These are unrefined grains that haven't had their bran and germ removed by milling. Whole grains are better sources of fiber and other important nutrients, such as selenium, potassium and magnesium. Whole grains are either single foods, such as brown rice and popcorn, or ingredients in products, such as buckwheat in pancakes or whole wheat in bread.

Refined grains. Refined grains are milled, a process that strips out both the bran and germ to give them a finer texture and extend their shelf life. The refining process also removes many nutrients, including fiber. Refined grains include white flour, white rice, white bread and degermed cornflower. Many breads, cereals, crackers, desserts and pastries are made with refined grains, too.

Enriched grains. Enriched means that some of the nutrients lost during processing are added back in. Some enriched grains are grains that have lost B vitamins added back in — but not the lost natural fiber. Fortifying means adding in nutrients that don't occur naturally in the food. Most refined grains are enriched, and many enriched grains also are fortified with other vitamins and minerals, such as folic acid and iron. Some countries require certain refined grains to be enriched. Whole grains may or may not be fortified.

Choosing whole grains

Make at least half the grains in your diet whole grains. Whole-grain versions of rice, bread, cereal, flour and pasta can be found at most grocery stores. Many whole-grain foods come ready to eat. These include a variety of breads, pastas and cereals.

Examples of whole grains include:

Barley

Brown rice

Buckwheat

Bulgur (cracked wheat)

Millet

Oatmeal

Popcorn

Whole-wheat bread, pasta or crackers

Wild rice

It's not always easy to tell what kind of grains a product has, especially bread. For instance, a brown bread isn't necessarily whole wheat — the color may come from added coloring. If you're not sure something has whole grains, check the product label or the Nutrition Facts panel. Look for the word "whole" on the package, and make sure whole grains appear among the first items in the ingredient list.